Steroidal anti-inflammatory drugs are commonly prescribed for inflammatory conditions such as arthritis, and for treatment of ocular inflammation due to mechanical or chemical irritants or immunological reactions resulting from such conditions as allergic conjunctivitis, herpes zoster keratitis, iritis, and corneal injury from chemical or thermal burns or penetration of foreign bodies. Anti-inflammatory steriods, however, are known to cause an elevation in IOP resulting in the condition known as ocular hypertension. While the term "ocular hypertension" indicates elevated IOP without optic nerve head damage or loss of vision, the condition is believed by the majority of ophthalmologists to represent the earliest phase in the onset of glaucoma, which is characterized by optic nerve damage and loss of vision, and which may lead to blindness. Patients with pre-existing glaucoma are particularly vulnerable to additional elevations in IOP caused by steroidal anti-inflammatory therapy. Also, in some susceptible individuals, topical steroids can induce an intractable glaucoma.
The increase in IOP often associated with the topical optical administration of steroidal anti-inflammatory agents can occur with all modes of administration of the drugs, including systemic (usually oral), local injection (e.g., depot injection), topical, aerosol or intravitreal administration.
Anti-inflammatory steroids include hydrocortisone, cortisone, prednisolone, prednisone, dexamethasone, methylprednisolone, triamcinolone, betamethasone, alclometasone, flunisolide, beclomethasone, clorocortolone, diflorasone, halcinonide, fluocinonide, flucinolone, desoximetasone, medrysone, paramethasone, 9,21-dichloro-17-[(2-furanylcarbonyl)oxy]-11-hydroxy-16.alpha.-methyl-preg na-1,4-diene-3,20-dione, and fluorometholone, and their pharmaceutically acceptable salts and esters.
Drugs currently employed to treat glaucoma, e.g., epinephrine and pilocarpine, are not particularly effective in lowering steroid-induced increases in IOP, and often produce serious side effects.